Mineral oil compositions



' incorporated therein,

' and aminor amount,.

Patented Aug. 5, 1952 MINERAL OIL COMPOSITIONS O Herschel G. Smith, Wallingford, and Troy L. Cantrell, Lansdowne, Pa., and John G. Peters, Audubon, N. J assignors to Gulf Oil Corporation, Pittsburgh, Pa., a corporation of Pennsylvania No Drawing. Application November 8, 1949, Serial No. 126,242

11 Claims. 1

This invention relates to improved mineral oil compositions, and more particularly, to improved mineral oils and mineral oil compositions containing minor amounts of improved agents which inhibit corrosion and prevent rust formation normally arising in the use of mineral oil lubricants.

Since simple mineral oils afford onlya limited protection to metal surfaces from rust and other types of corrosion, many so-called anti-corrosive lubricating oils have been proposed consisting of mineral oils and various added constituents. These have not been entirely satisfactory.

' We have discovered certain new improvement agents for mineral, oils which are particularly advantageousinthe commercial preparation of various lubricants, protective coating compositions and other useful mineral oil compositions.

Our new agents can be readily incorporated in various mineral oils and oil compositions. When even in very small amounts, these agents markedly improve the rust protective properties thereof. Moreover, they are also capable of imparting other useful and advantageous properties to the mineral oils and oil compositions in which they are incorporated.

An object of this invention is to provide an improved oil composition which is useful and advantageous in protecting both ferrous and nonferrous metals from rust, corrosion and wear.

It is another object of this invention to provide improved mineral oil compositions containing agents capable of conferring marked anticorrosive properties on the compositions.

These and other objects are achieved by the provision of an improved mineral oil composition comprising a major amount of a mineral oil sufficient to confer corrosion inhibiting properties on the mineral oil, of a phthalamidate-substituted ortho phosphoric acid having the formula:

or the salts thereoffwherein Misla of alkyl and alkenyl radicals" containing from 8 to 22 carbon atoms, and R1 is a member of the class consisting of hydrogen and alkyl radicals. The above acids and salts are described and claimed in our copending application, Serial No. 126,241, filed of even 'date herewith.

The improvement agents of this invention, the so-called phthalamidate-substituted ortho phosphoric acids, can be prepared as follows. There is first prepared a divalent metal salt of an N- alkyl or alkenyl, N-alkylol phthalamidic acid,

divalent 'metal, R1 is selected from the group consisting i. e., a compound of the formula:

wherein M isa divalent metal, R1 is selected from the group consisting ofalkyl and alkenyl radicals containing from 8 to 22 carbon atoms, and R2 is a member of the class consisting of hydrogen and alkyl radicals. The method of preparation of such compounds is described in our U. S. Patent 2,408,103. The above phthalamidic acid salts are then reacted with an esterifying derivative of ortho phosphoric acid to form the phthalamidatesubstituted ortho phosphoric acid. If a salt of the resulting acid is desired, the acid is neutralized with an organic or inorganic base.

It will be noted that the N-alkylol grouping in the above-described phthalamidate saltresults in the presence of two hydroxylgroups in the; molecule. Accordingly; in preparing the phthalamidate substituted ortho f phosphoric acids of this invention, the two hydroxyl groups in the phthalamidate salt are esterifie'd'by a suitable esterifying derivative of ortho phosphoric acid, for example, phosphorus pentoxide, phorphorus ox'ychloride or thelike. Of'course, when phosphorus oxychloride is used, the residual chlorine is hydrolyzed off, in 'a' manner known to the art, to obtain ourphthalamidate-substituted ortho phosphoric acid. The amount of the ortho phosphoric acid derivative employed is such as to esterify both free hydroxyl groups in the above phthalamidate salt. Thus, for each mol of the phthalamidate salt employed, there is employed one-half mol of phosphorus pentoxide or one mol of phosphorus oxychloride.

The salts of the phthalamidate-substituted ortho phosphoric acids of our invention are simply prepared by neutralization with a suitable 2,606,152 3 4 base. Either inorganic bases or organic nitrogen 35 parts of phosphorus pentoxide dispersed in 20 bases are employed. Inorganic salts can also be parts of a mineral lubricating oil having a visprepared by metathesis of an alkali metal salt cosity of 150 S. U. S. at 100 F. were added to of the phthalamidate-substituted ortho phosthe phthalamidate in the reaction vessel over a phoric acid and a water-solubleinorganic salt 5 period of 2 hours. The temperature was then of another metal. f raised to 220 F. to complete'the reaction. The These"phthalamidate-substituted ortho phosproduct obtained was a light brown solid of inphoric acids and their salts are excellent imdefinite melting point, insoluble in water and alprovement agents for mineral oils of various cohol, but soluble in benzene, naphtha, and minkinds and they can be easily incorporated in eral lubricating oils. It had the formula:

these improvement agents are readily'soluble in mineral oils, particularly naphthenic type oils.

We find it convenient to prepare solutions of our new additives in a-mineral oil by forming them in situ in the oil. In such processes the phthalamidatesalt is first dissolved in a mineral oil, such as a mineral lubricating oil, naphtha, Stoddard solvent; etc. and then thephosphorus pentoxide is added, the mixture being stirred and i u maintained at the desired temperature until the gg gfiggg ggg fi 2 gggg gg ggg zi fififi reaction is complete. The mineral oil solution making the calcium Salt of the reaction of the resulting phthalamidate-substituted ortho not The product a then diluted t 950 phosphoric acid may then be neutralized with a parts f benzene, the Water layer was drawn Ofi baseand the benzene layer was filtered. The filtered AS class the new fields and Salts of 0111 benzene solution was then transferred to an iron en o a e light brown Solids 0 indefinite meltstirring still and the benzene removed under a ing Point ey are 501111016 in mineral lubr cafi- 4 vacuum of 20 inches of mercury. The salt 0bingoils, naphtha, carbon tetrachloride, carbon tained as a residue was a neutral light brown disulfide and benzene, but are insoluble in alcosolid of indefinite melting point. It had the 01- 1101, water, acetone and. glycol. lowing formula: Y

Into an iron reaction vessel there was charged 5 892 parts of the calcium salt of N-cetyl, N-propanol phthalamidic acid which was then heated to 170 F. Then 153 parts of phosphorus oxychloride were added and the temperature raised to 220 F. to complete the reaction. Thereafter 0 148 parts of hydrated lime in a percent water slurry were added to remove the-hydrochloric E) V o o=i H n o=o C8 CH3(OH7) CHg-N-CHr-O-P-O--CH:1LCH2(QH2)14CH3 The following examples. are illustrative of the V EXAMRLE H preparation' of a few of our improveme t agents. However, our 'invention'isino't to be 'limited' to these particularexamples. Unless otherwise in- Into an iron reaction vessel were placed 8'32 parts of the calcium salt of N-dodecyl, N-propanol phthalamidic acid, parts of 150 viscosity SUS/ F. mineral lubricating oil, and '22 parts of phosphorus pentoxide. The reactants were p heated to a temperature of 230F. until the re- Into 'an iron .reaction;. vessel,- ft-here- .were action was complete. The reaction product was charged 892 .parts of thecalci'um saltzof N cetyl, then neutralized with 6 parts of calcium hydrox- N-propanolphthalamidic acidr-which, ':was.'. then ide at 240 F. and filtered. The compound so heated ,to' a temperature 0fz1110 Thereafter 5 prepared had the formula:

dicated," all .parts are f'by weight.

I O=C H H H 11- (3:0

.5 andits solution in the mineral oil had the following properties:

Gravity, Al=I -1 18.0

Viscosity, SUV:

100 F. 283.3 210 51.0 Color, NPA 3.75 Neutralization No. 4.04 Ash, percent 2.91 pH value a. 7.?

EXAMPLE IV "'Into an-iron reaction vessel were placed 832 1 whereinlt is the -co co radical;-and its solution n=,the mineral oil had the followingproperties:

Gravity. API 20.3, Viscosity. SUV: r

1 oo, F 307 210 v 52.4 Color, NPA 3.25 Neutralization No 10.52 Ash as oxide, per cent 1.8 pH value.-- r I 7.7

V The N-alkyl or alkenyl, N-alkylol phthalamidic aciddivalent metal salts from which our phthalamidate-substituted 'ortho phosphoric acid is 'madecan be obtained from any suitable source.

As indicated hereinabove, one convenient method of preparing these divalent metal salts is described in our U. S. Patent 2,408,103. By this method secondary alkyl, alkylol amines are first prepared by reacting alkylene oxides, such as ethylene oxide, propylene oxide, butylene oxide, etc., with rimary alkyl or alkenyl amines. Suitable primary alkyl or alkenyl amines are those having from 8 to 22 carbon atoms, such as octyl, decyl, decenyl, undecenyl, dodecyl (lauryl), dodecenyl, tetradecyl, hexadecyl (cetyl), octadecyl (stearyl). 9,10-octadecenyl (oleyl), eicosyl, eicosenyl, docosyl, etc. The resulting alkylol amines are then reacted with phthalic anhydride in sub,-

stantially equimolecular amounts to form. a

mono-amide of phthalic acid, namely the desired N-alkyl or alkenyl, N alkylol phthalamidic acid,

which is then converted to the divalent metal salt. Any divalent metal can be used in the preparation of the salt including calcium, magnesium, barium, lead, cadmium, cpper,. tin, strontium, iron, zinc, cobalt, etc.

6 3 As ha e n ca emhe i ve. v r u salts of the phthalamidate-substituted ortho phosphoric acids of our invention are simply prepared by neutralization or metathesis. For example, alkali metal and ammonium salts can be prepared by neutralizing the acid with a hydroxide or carbonate of an alkali metal such as sodium, potassium, lithium, ammonium, etc. Other suitable hydroxides yielding valuable salts are calcium, barium, magnesium, strontium and aluminum hydroxides. Salts of these metals as well as salts of zinc, copper, tin, lead, iron, cobalt, nickel, manganese, cadmium, mercury, bismuth, vanadium, chromium, etc., can conveniently be preparedby metathesis of a water-soluble inorganic salt of such metal with an alkali metal salt of our phthalamidate-substituted ortho phosphoric acid.

Organic nitrogen bases also yield valuable addition salts. Such bases include primary, secondary and tertiary aliphatic and aromatic amines, alkylol amines and heterocyclic nitrogen bases. Primary alkyl amines such as ethyl, butyl, amyl, hexyl, cyclohexyl, heptyl, octyl, decyl, undecyl, lauryl, tetradecyl, hexadecyl, oct'adecyl and eicosyl are suitable. Mixtures of primary alkyl amines, such as are present in commercially available amines derived from fatty acids by well known methods, make desirable salts. For example, 'cocoamine, derived from coconut oil fatty facldsand containing primarily dodecyl amine with smaller: amounts of homologues, yields a preferred salt; Primary alkenyl amines corresponding to the primary alkyl amines, such as undecenyl, oleyl, etc.,can also be employed. A preferred group is the primary alkyl or alkenyl amines having from 8 to 22 carbon atoms. Salts derived from secondary and tertiary amines whether aliphatic or aromatic, such as the diand tri-ethanolamines, dicyclohexyl amine, aniline, N-alkyl and N-dialkylarylamines, e. g., N- ethylaniline, N-dimethylaniline, are satisfactory. A valuable class of salts is derived from heterocyclic nitrogen bases such as pyridine, picoline, ethyl pyridine, lutidine, aldehydine, parvoline, quinoline, quinaldine, lepidine, isoquinoline, nicotine, piperidine, morpholine, N-phenyl morpholine, etc.

A wide range of improved antirust or anticorrosive compositions can be readily prepared .by incorporating minor amounts-of our improvement agents in suitable oils and oil compositions. Moreover, such improved compositions effectively protect ferrous and non-ferrous metals aga nst rusting and corrosion, even when exposed to salt water and other severe conditions. When applied to such metals they tightly adhere to the metal, forming a resistant film which protects the metals even when they are exposed to drastic conditions. Generally, our new compounds are employed in amounts sufficient to give the desired corrosion inhibiting effect, say from 0.01 to 10 per cent by weight of the composition in which they are incorporated.

The outstanding improvements obtained by the present invention are illustrated in the following'examples, which are typical of our improved oils.

EXAIWPLE V An improved mineral lubricating oil was prepared by the addition of 0.3 per cent of an additive prepared according to Example III to a mineral lubricating. oil base. The properties of the 7 proved oil and thetherefrom were asrouows:

proved oil prepared vHropcrtzes Uni'n- Inhibliibited 'ited -Oil Oil Gravity, API 32.0 .31. 8 Viscosity, SUV- 100-F 152.0 150.9 210 43.4 v 43.3 Viscosity Inde 105 100 0111', F, +15 '+15 Color, NBA- 1. 25. 1. 25 Copper strip Test, 12 passes passes Neutralization N o. "0.01 '0.

CORROSION TESTS Corrosion Test, ASTM D 6fi5 47-l:

Distilled Water- Appearance of Steel Rod rusted bright 7 Area Rlisted, Percent 100 Synthetic Sea Water- Appearanceof Steelfiod rusted bright V j. ,Area'Rusted, Percent V 100' 0 .Static Rust Test-(0rd. Spec. 814, F a) fails passes An' improved mineral vliib'ricating oil was prepared by the addition of 0.3 per cent of an additive prepared according to Example IV .to a mineral lubricating oil lease. [The properties ofthe unimproved oil and the improved oil prepared therefrom were as follows:

Properties 8 tive preparedaccording to Example Ito a min-- eral lubricating oil base. The properties of the unimproved oil and the improved oil prepared therefrom were as follows: s a

Properties Unininhibhibite'd itd Oil 011 Gravity, API 31.8 31. 7 Viscosity, SUV:

100 151. 7 153.2 43 5 43. 7 100. 100 +15 r, r 1.25 CoppenStnp Test, 212 F., 3 Hr passes passes Neutralization-Non.". s e 0. 01- 0.19

oORPOsION TESTS Corrosion Test, AsTM'D 565-41 T:

Distilled Water- Steel Rod, Appearance rusted bright Area Rusted, Percent 1 0 Synthetic Sea Water- Steel Rod, Appearance rusted bright Area Rusted, Percent 100 0 Static Rust Test (0rd. Spec. 814, F2a) fails passes As shown by the tabulation of properties in Examples V, VI and VII above, the incorporation of our improvement agents in mineral lubricating oils, in the amounts necessary to impart marked rust preventive qualities thereto, did not sub- Ux-lim m stantially change any of the other properties of hibi ted 'itetl the'oils. However, the-oorrosion-t'ests set for'th v p v I 9' above, clearly show the markedly'improved rust o p p 318 318 preventive qualities of the improved oils. When subjected to the various standard tests used-in ion evaluating commercial oils, they successfully 5 v i b passed all of them; even the most -dras tici As shown by theresults-obtained inthecorrosion passes passes 45 tests, rusting of steel is entirely prevented with W the improved-oils; '-For-these reasons,such m proved "oils are advantageously used as "turfbine' CQRBVLOSIONYTESTS oils, particularly since the oils "are resistant to i v emulsification. I Our improved oils have other "s'uiperior propc "jgTesLASTMDGB J'IT: v I o..

a i s tilled Water- V V V ort es. For example, theyhave excellent lllbIlbng g eating qualities when evaluated bythestandard Synthetic Sea Water- I l b ht "Falex WGEtf'lJ-Efit. when so evaluated the test s i z 3 53 o clata'o'btamezi areias'follows'theoilused'in the Static Rust Test (0rd. Spec. 8 14, F 29.) rails p e 55 following being ani myi'efined mineral monast- H r. .7 mg oil having a viscosity "or 300 SUS at 160 emitter il lreitd Unin- H witi1'10'7 of with 10 of 'gff Salter-fixsdltol v ample III ample-IV Inspection:

Falex Wear Tst, Diy Metliod 500 Lb. Gauge Load for 15 Min.

I Wear, No. ol'Teeth '3 4 v Gauge Lo'a'dat Seiznre, Lb 1,350 4 350 Falex Wear Test, Wet Method v i 500 Lb. Gauge Load for '15 Min. v

Wear,No.oTee'th 0 '6 Gauge Load at selzure Lbr 4,550 o A p.300

In this test, idiper cent ofwvater ispreseiit in the oil during the test.

. EXAM? LE "V-I l An improved mineral lubricating oil was .i r'epared by the addition of 0.3 per eentofan addi= The above examples are itypica'l embodiments of the present invention and various oth'er-em bodiments 'willroccur" to those skilled m the art; The examples givenshowzthat'a plurality-er ed vantageous properties can be imparted to mineral oils by incorporating our new'improvement agents therein.

Our new agents are useful and advantageous in preparing improved motor oils for lubricating automotive, aviation and diesel engines. Such improved oils can be readily prepared by incorporating a small percentage of the improvement agent in a suitable mineral lubricating oil, usual- 1y from 0.01 to per cent by weight of the oil. In addition to mineral lubricating oils our improvement agents are readily soluble in various hydrocarbon oils; and they are also readily miscible with waxes, petrolatum, and greases. Thus, various slushing and coating compositions having improved anti-corrosive properties can be prepared in' accordance with our invention. Our new compounds may be incorporated in various mineral oils, such as gasoline, kerosene, diesel fuel and other fuels; Stoddard solvent, V. M. & P. naphtha and like volatile hydrocarbon solvents for the preparation of simple anti-corrosive coating compositions; and, of course, all types of mineral lubricating oils, such as turbine oils, I

motor oils, aviation oils, diesel oils, etc.

- Inthe preparation of mineral lubricating oils in accordance with our invention other known addition agents such as viscosity index improvers,

pourpoint depressants,- anti-foam agents, and the like may be added without departing'from the spirit of our invention.

While our invention has been described above with reference to various representative examples and embodiments, it will be understood that the invention is not limited to such illustrative examples and embodiments, but may be variously practiced within the scope of the claims herein made.

We claim:

1. An improved mineral oil composition comprising a major amount of a mineral oil and a minor amount, sufficient to confer corrosion inhibiting properties, of an oil soluble compound selected from the group consisting of an acid having the formula:

and salts thereof, wherein M is a divalent metal,

R1 is selected from the group consisting of alkyl .fl 0 3. improvedmineral oil composition comprising amajoramount of -a,mineral oil, and a niinb ga u t ffi ient t o e or n .hibitingpropertiea;of;an oil soluble metal salt of a compound having-the formula; I

minor-amounusufiicientto confer corrosion inhibiting properties, of a'salt of an" organic nitrogcn'base'and an acid-havingtheformula:

wherein M is a divalent metal and R1 is selected from the group consisting of alkyl and alkenyl radicals having from 8 to 22 carbon atoms.

6. The composition of claim 5, wherein the mineral oil is an oil of lubricating viscosity, M is an alkaline earth metal, and the organic nitrogen base is a primary aliphatic amine having from 8 to 22 carbon atoms.

7. An improved mineral oil composition comprising a major amount of a mineral oil, and a minor amount, sufficient to confer corrosion inhibiting properties, of a substituted ortho phosphorio acid having the formula:

wherein M is an alkaline earth metal.

9. A lubricant composition in accordance with claima' where'in M=is calcium.

105 Alubricantcomposition comprising arnajor amount of a mineral lubricating oil and aminor amount, from'DiOlto 'per cent by weight, ofan amine salt of a substitutedortho phosphoric acid, said salthaving the formula:

wherein, R is an aliphatic radicalhavingefrom 8 to 22 carbon atoms; and "Misha. divalent metal.

11. Aniimproved' mineral oil composition comprising a major amount of a; mineral oil and a minor amount, suflicient to confer corrosion inhibiting properties, of a cocoamine salt of a sub- 12 stitutedortho phosphonic acid, said salt having the formula:

wherein R is the coco ra.dical.

I-IERSCHEL G. TROY L. CANTRELL.

JOHN G. PETERS.

REFERENCES CITED 7 The following references are of record in the file of this patent:

UNITED STATES PATENTS Smith et a1. Sept. 24; 1946 

1. AN IMPROVED MINERAL OIL COMPOSITION COMPRISING A MAJOR AMOUNT OF A MINERAL OIL AND A MINOR AMOUNT, SUFFICIENT TO CONFER CORROSION INHIBITING PROPERTIES, OF AN OIL SOLUBLE COMPOUND SELECTED FROM THE GROUP CONSISTING OF AN ACID HAVING THE FORMULA: 